皮质对水的不透性:第二次观察
Lydia G Gibson1, Elena K DeFilippo1, Austin Mahajan2
1Department of Biological Sciences, Kent State University, Kent, Ohio, USA.
概括
管,像收集管和上升的亨尔环一样,是水的透性,挑战传统的观点. 这种有限的水透性允许显著的液体再吸收到高压神经髓中.
科学领域:
- 腎臟病學 (nephrology) 是一種醫學專業.
- 脏生理学 脏生理学
- 细胞生物学 细胞生物学
背景情况:
- 亨勒环的透性上升的肢体对于脏反流的繁殖至关重要.
- 管道的水透性,特别是收集管道,是有争议的.
- 脂二层是细胞膜的基础,具有固有的水透性.
研究的目的:
- 重新评估管的水透性,特别是亨尔环的上升端和收集管道.
- 为了确定这些管道是否表现出异常的抵抗水流.
- 评估管道水透性对液再吸收的贡献.
主要方法:
- 分析已公布的关于水透性的数据.
- 对透冲击实验的审查.
- 根据水的透性,估计液体的再吸收.
主要成果:
- 管,包括收集管和上升的亨尔环,具有有限的水透性.
- 透冲击实验证实,水的透性足以产生体积调节效应.
- 估计20-50%的管状液体可以被再吸收到高性脑髓中.
结论:
- 收集管道和上升的亨尔环并不是对水不透的.
- 这些上皮质不会表现出异常的对水流的抵抗力.
- 完好无损的脏中的未动的层可能会导致感知到的低透性.
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